Pathomorphological diagnostics of enteritis of viral etiology in dogs

The article presents the results of the study of pathomorphological changes in organs and tissues of dogs at parvovirus and coronavirus infections. The pathoanatomical section and histological examination of pathological material selected from cadavers of dogs of different breeds and sex between 2 to 6 months who died with signs of infectious diarrhea were conducted. Pathomorphological study was performed only on cadavers of animals in which the life using PCR in stool specimens was established clinical diagnosis – parvovirus enteritis (n = 13) and coronavirus enteritis (n = 7). After selection of the pathological material, it was immediately fixed in a 10% aqueous solution of neutral formalin followed by pouring into a sealing medium (paraffin). The obtained histological sections were stained with hematoxylin and eosin according to standard prescriptions. The general histological structure and microstructural changes in histological preparations were studied under a light microscope. Histological studies have been confirmed and supplemented with pathoanatomical diagnoses, established after autopsies of bodies of dead animals. The most pronounced lesions and typical change in all dead dogs fixed contact in the small intestine (jejunum and to the ileum) and the regional lymph nodes. In addition, in the case of coronavirus infection, changes in the spleen are detected. According to the results of our study, the morphological criteria, on which the pathomorphological diagnosis of parvovirus infection in dogs is based include: hemorrhagic jejuno-ileitis; hemorrhage in the serous and mucous membrane of the small intestine; hemorrhagic mesenteric lymphadenitis; depletion and necrosis of lymphoid tissue. It is shown that the morphological manifestations of coronavirus infection in the dead dogs are with the following signs: the presence of exudative inflammation in the small intestine in the form serous-catarrhal or serous-fibrinous jejuno-ileitis; hyperplasia of single and congested lymphoid nodes of the mucous membrane of the small intestine; hyperplasia and serous-hemorrhagic mesenteric lymphadenitis; hemorrhagic infarcts in the spleen parenchyma; hyperplasia of lymphoid tissue; hemorrhage in the serous membrane of the small intestine; dehydration. Not typical, but constant morphological signs of enteritis, which arose as a result of circulatory disorders and heart failure were: passive venous congestion of the liver and kidney; degenerative processes in the liver and kidney parenchyma; pulmonary edema.